The use of kitchen faucet is mainly used to supply clean water. For drinking or cooking water, generally, a water clean device is added to the kitchen. The device has a clean water supply tube which is located near the faucet so that the user can operate easily. However, this will make the space of the kitchen become smaller so as to interfere the operation of users.
In the prior art, the general water supplying tube and clean water supply tube are coaxial and are connected to a faucet which serves to switch the supply of general water and clean water. In this arrangement, a general water control stud and a clean water control stud are arranged with the faucet so that the arrangement of elements are complicated and yield ratio is low. Moreover, the control handles for general water and clean water at lateral sides of a faucet have difference in position arrangement. However, two handles are used so that users often make mistakes in selecting a desired handle to supply desired water.